Research on Controllable Artificial Chalking Method for Silicone Rubber

Chalking of silicone rubber (SR) is a universal and important aging phenomenon. However, performing chalking simulations to study the aging performance of SR in the laboratory is difficult. In this study, a controllable artificial chalking method, which was based on selective scission reactions using methylcyclohexane (MCH) and diethylamine (DEA) as solvents and tetramethylammonium hydroxide (TMAH) as the catalyst, was developed. By controlling the ratio between DEA and MCH, different chalking degrees of SR could be realized artificially. Macroscopic observation, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectroscopy (FTIR) were conducted to compare the differences of samples with various chalking degrees. Furthermore, the control mechanism of the degree of chalking and the function of DEA during the artificial chalking process was elucidated. The results demonstrated that the artificial chalking method was feasible and could help identify the antiaging ability of SR.